The subject matter of the present invention is a device for uncoiling a paper strip from a coil.
More specifically, the present invention is concerned with a device of the kind forming the subject matter of the publication EP-A-0384533 (U.S. patent application Ser. No. 07/482,229 filed on Feb. 20, 1990 in the name of the present Applicant and now U.S. Pat. No. 5,139,207 entitled "Unwinding Device For Paper Reels" specification and drawings of the above mentioned publication (application), now patent. As noted, the aforesaid U.S. Patent is concerned with an unwinding device for a reel formed of uniformly continuous paper. The device forming the subject matter of the afore-noted U.S. Patent advantageously solved the problems arising from the support and the moving of a paper coil for the uncoiling from the paper coil of a continuous paper strip for the feeding thereof to an apparatus which uses the paper. The last one, for example, had been considered as consisting of a printer, such as a laser printer or the like.
The problems arise chiefly from the not negligible or large size and, above all, from the weight of the coils prior to their uncoiling, as the weight can be of the order of many quintals (hundredweights).
It has been however noticed that when the paper on the paper coil is about to be exhausted its weight is no longer sufficient to assure a proper support on a suitable supporting means controlling contemporaneously the uncoiling thereof and, while such an uncoiling of the paper coil is interrupted, the coil, itself in a substantially unwound condition, is driven to the fore portion of the device by the supporting means themselves, and then stops the feeding of the paper to the printer.
While what is above disclosed is particularly advantageous because it is both not easily forecastable that when uncoiling and movement can occur, and while a sudden stoppage of paper fed to the printer can damage the same, it is desirable to avoid such sudden stoppage.
Further, there is also the noticeable drawback arising from the not negligible unused paper quantity together with the apparent economic damage.
It has been devised, and it is the subject matter of the present invention, to a provide an improved device following the teachings according to the above mentioned patent application which device has been improved by providing it with means and structure for eliminating the above mentioned drawbacks.
The device according to the present invention is thus characterized in that it comprises, providing downstream of the paper coil supporting means in the device of the aforementioned U.S. Patent for controlling the uncoiling of the paper from the paper coil of the paper strip for feeding the printer, novel means for receiving and supporting the coil about to be exhausted, while allowing the rotation and uncoiling of the coil in order not to interrupt the paper strip uncoiling therefrom, and further providing sensing means which are actuated by the presence of the coil and sensing means for sensing the presence of paper on the coil to control the device stopping the uncoiling of the paper coil when the coil is substantially exhausted.